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_______________ INTERNATIONAL TELECOMMUNICATION UNION CCITT I.113 THE INTERNATIONAL TELEGRAPH AND TELEPHONE CONSULTATIVE COMMITTEE INTEGRATED SERVICES DIGITAL NETWORK (ISDN) GENERAL STRUCTURE AND SERVICE CAPABILITIES VOCABULARY OF TERMS FOR BROADBAND ASPECTS OF ISDN Recommendation I.113 Geneva, 1991 Printed in Switzerland FOREWORD The CCITT (the International Telegraph and Telephone Consultative Committee) is a permanent organ of the Interna- tional Telecommunication Union (ITU). CCITT is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The Plenary Assembly of CCITT which meets every four years, establishes the topics for study and approves Recommendations prepared by its Study Groups. The approval of Recommendations by the members of CCITT between Plenary Assemblies is covered by the procedure laid down in CCITT Resolution No. 2 (Melbourne, 1988). Recommendation I.113 was prepared by Study Group XVIII and was approved under the Resolution No. 2 procedure on the 5th of April 1991. ___________________ CCITT NOTES 1) In this Recommendation, the expression "Administration" is used for conciseness to indicate both a telecommunica- tion Administration and a recognized private operating agency. 2) A list of abbreviations used in this Recommendation can be found in Annex A. aITU1991 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. Preamble to B-ISDN Recommendations In 1990, CCITT SG XVIII approved a first set of Recommendations on B-ISDN. These are: I.113 û Vocabulary of terms for broadband aspects of ISDN I.121 û Broadband aspects of ISDN I.150 û B-ISDN asynchronous transfer mode functional characteristics I.211 û B-ISDN service aspects I.311 û B-ISDN general network aspects I.321 û B-ISDN Protocol Reference Model and its application I.327 û B-ISDN functional architecture I.361 û B-ISDN ATM Layer specification I.362 û B-ISDN ATM Adaptation Layer (AAL) functional description I.363 û B-ISDN ATM Adaptation Layer (AAL) specification I.413 û B-ISDN user-network interface I.432 û B-ISDN user-network interface û Physical Layer specification I.610 û Operation and maintenance principles of B-ISDN access These Recommendations address general B-ISDN aspects as well as specific service- and network-ori- ented issues, the fundamental characteristics of the asynchronous transfer mode (ATM), a first set of relevant ATM oriented parameters and their application at the user-network interface as well as impact on operation and maintenance of the B-ISDN access. They are an integral part of the well established I-Series Recommen- dations. The set of Recommendations are intended to serve as a consolidated basis for ongoing work relative to B-ISDN both within CCITT and in other organizations. They may also be used as a first basis towards the devel- opment of network elements. CCITT will continue to further develop and complete these Recommendations in areas where there are unresolved issues and develop additional Recommendations on B-ISDN in the I-Series and other series in the future. PAGE BLANCHE Recommendation I.113 Recommendation I.113 VOCABULARY OF TERMS FOR BROADBAND ASPECTS OF ISDN 1 Introduction This Recommendation consists primarily of those terms and definitions that are considered essential to the understanding and application of the principles of broadband aspects of the integrated services digital network (BISDN). They are not exclusive to B-ISDN and are recommended also for application, in so far as they are rel- evant, to other types of telecommunication networks. Included are terms that may already be defined in other CCITT/CCIR Recommendations. However, the definitions given here embrace only the essential concepts and on that basis it is considered that they are not inconsistent with the more specialized definitions that appear in those Recommendations. According to the conventions applied in this Recommendation, any term in common usage, but whose use is deprecated, is shown in brackets as in the following example: "broadband [wideband]". Where a truncated term is widely used in an understood context the complete term is quoted following the colloquial form, for example, "contribution, contribution application". Some definitions include terms in italics face to indicate that these terms are defined elsewhere in this Recommendation. Annex A contains an alphabetical list of all the terms contained in this Recommendation. Annex B contains a list of abbreviations which are used in B-ISDN Recommendations. 2 Vocabulary of terms This section is divided into two sub-sections, 2.1 Services, and 2.2Interfaces, channels and transfer modes. Within each sub-section the terms are listed and defined. 2.1 Services 101 broadband [wideband] F: large bande S: banda ancha A service or system requiring transmission channels capable of supporting rates greater than the pri- mary rate. 102 broadcast F: diffusion S: difusi≤n A value of the service attribute "communication configuration", which denotes unidirectional distribu- tion to all users. Note û This term should not be confused with the term "broadcasting service" as defined in the ITU Radio Regulations. 103 connectionless service F: service sans connexion S: servicio sin conexi≤n A service which allows the transfer of information among service users without the need for end-to- end call establishment procedures. Note û Connectionless services may be used to support both interactive and distribution services. 104 constant bit rate service F: service α dΘbit constant S: servicio de velocidad binaria constante A type of telecommunication service characterized by a service bit rate specified by a constant value. 105 contribution, contribution application F: contribution S: contribuci≤n; aplicaci≤n de contribuci≤n Use of a broadband service or channel for transferring audio or video information to a user for fur- ther post-production processing and subsequent distribution. 106 conversational service F: service conversationnel S: servicio conversacional An interactive service which provides for bidirectional communication by means of real-time (no store-and-forward) end-to-end information transfer from user to user. 107 distribution, distribution application F: distribution; application de distribution S: distribuci≤n; aplicaci≤n de distribuci≤n Use of a broadband service or channel for transferring audio, video or other information to a user or a number of users who will not be expected to apply post-production processing to the information. 108 distribution service F: service de distribution S: servicio de distribuci≤n Service characterized by the unidirectional flow of information from a given point in the network to other (multiple) locations. Distribution services are subdivided into two classes: distribution services without user individual presentation control and distribution services with user individual presentation control. 109 distribution service with user individual presentation control F: service distribuΘ avec contr⌠le de prΘsentation par l'usager S: servicio de distribuci≤n con control de la presentaci≤n por el usuario A distribution service in which the information is provided as a sequence of information entities e.g. frames with cyclical repetition, so that the user has the ability to select individual information entities and can control the start and order of the information. 110 distribution service without user individual presentation control F: service distribuΘ sans contr⌠le de prΘsentation par l'usager S: servicio de distribuci≤n sin control de la presentaci≤n por el usuario A distribution service which users can access without having any control over the start and order of the presentation of the distributed information. 111 enhanced-quality television F: tΘlΘvision de qualitΘ amΘliorΘe S: televisi≤n de calidad mejorada Television of quality superior to existing-quality television, but less than the quality of high-definition television. 112 existing-quality television F: tΘlΘvision de qualitΘ conventionnelle S: televisi≤n de calidad convencional Television as defined in conventional 625-line and 525-line television standards, such as NTSC, PAL and SECAM. 113 interactive service F: service interactif S: servicio interactivo A service which provides the means for bidirectional exchange of information between users or between users and hosts. Interactive services are subdivided into three classes of services: conversational ser- vices, messaging services and retrieval services. 114 messaging service F: service de messagerie S: servicio de mensajerφa An interactive service which offers user-to-user communication between individual users via storage units with store-and-forward, mailbox and/or message handling, (e.g. information editing, processing and conversion) functions. 115 mixed document F: document mixte S: documento mixto A document that may contain text, graphics, data, image and moving picture information as well as voice annotation 116 multimedia service F: service multimΘdia S: servicio multimedio A service in which the interchanged information consists of more than one type, such as text, graph- ics, sound, image and video. 117 multipoint F: multipoint S: multipunto A value of the attribute "communication configuration" which denotes that the communication involves more than two network terminations. 118 post-production processing F: post-production (traitement aprΦs production) S: tratamiento de posproducci≤n Further processing of contributed audio and video information, to change the form or presentation of the information prior to its final utilization. 119 retrieval service F: service de consultation S: servicio de consulta An interactive service which provides the capability of accessing information stored in data base cen- tres. This information will be sent to the user on demand only. The information can be retrieved on an indi- vidual basis, i.e.the time at which an information sequence is to start is under the control of the user. 120 service bit rate F: dΘbit de service S: velocidad binaria de servicio The bit rate which is available to a user for the transfer of user information. 121 sound retrieval service F: service de consultation de programmes sonores S: servicio de consulta de programas sonoros On-demand (user initiated) retrieval of music and other audio information. 122 variable bit rate service F: service α dΘbit variable S: servicio de velocidad binaria variable A type of telecommunication service characterized by a service bit rate specified by statistically expressed parameters which allow the bit rate to vary within defined limits. 123 videomessaging F: messagerie vidΘo S: videomensajerφa A messaging service for the transfer for moving pictures with or without other information. 2.2 Interfaces, channels and transfer modes 201 asynchronous time-division multiplexing F: multiplexage temporel asynchrone S: multiplexaci≤n asφncrona por divisi≤n en el tiempo; multiplexaci≤n temporal asφncrona A multiplexing technique in which a transmission capability is organized in undedicated slots filled with cells with respect to each application's instantaneous real need. In this case, the terminal equipment (i.e. the customer application) defines the actual transmitted bit rate, whatever this rate is, possibly variable dur- ing the communication. This technique carries a labelled interface structure over a frame or a self-delineating labelled interface. 202 asynchronous transfer mode (ATM) F: mode de transfert asynchrone (ATM) S: modo de transferencia asφncrono (MTA) A transfer mode in which the information is organized into cells; it is asynchronous in the sense that the recurrence of cells containing information from an individual user is not necessarily periodic. 203 block F: bloc S: bloque A unit of information consisting of a header and an information field. 204 block payload F: capacitΘ utile de bloc S: cabida ·til del bloque; contenido ·til del bloque The bits in the information field within a block. 205 broadband access F: accΦs large bande S: acceso de banda ancha An ISDN access able to contain at least one channel capable of supporting a rate greater than the pri- mary rate, or supporting an equivalent information transfer rate. 206 broadband communication channel F: canal de communication large bande S: canal de comunicaci≤n de banda ancha A specific portion of the information payload capacity, available to the user for ISDN services. A broadband communication channel exists only during a call, as set-up by a signalling or administrative pro- cedure. 207 cell F: cellule S: cΘlula A block of fixed length. It is identified by a label at the asynchronous transfer mode layer of the B- ISDN protocol reference model. 208 cell delineation F: cadrage cellule S: delimitaci≤n de la cΘlula The identification of cell boundaries in a cell stream. 209 circuit transfer mode F: mode de transfert par circuit S: modo de transferencia circuito; modo de transferencia por circuitos A transfer mode in which transmission and switching functions are achieved by permanent allocation of channels/bandwidth between the connections. 210 connection admission control F: contr⌠le d'admission des connexions S: control de admisi≤n de una conexi≤n The procedure within the control part of network nodes used to decide whether or not a request for a (virtual) connection can be accepted based on the requested usage parameters and already established con- nections. 211 deterministic; ATM deterministic F: dΘterministe; ATM dΘterministe S: determinφstico; MTA determinφstico A mode of the asynchronous transfer mode in which a constant information transfer capacity expressed in terms of a predetermined limiting value for a given service is provided to the user throughout a call. 212 frame F: trame S: trama A block of variable length identified by a label at layer 2 of the OSI reference model, e.g. an HDLC block. 213 framed interface F: interface tramΘe S: interfaz entramado An interface where the serial bit stream is segmented into periodic physical frames. Each frame is divided by a fixed partition into an overhead and an information payload portion. 214 general broadcast signalling virtual channel F: canal virtuel de diffusion gΘnΘrale de la signalisation S: canal virtual de se±alizaci≤n de difusi≤n general A virtual channel independent of service profiles and used for broadcast signalling. 215 header, cell header F: en-tΩte; en-tΩte de cellule S: encabezamiento; encabezamiento de cΘlula The bits within a cell allocated for functions required to transfer the cell payload within the network. 216 hybrid interface structure F: structure d'interface hybride S: estructura hφbrida de interfaz An interface structure which has a mixture of labelled channels and positioned channels. 217 information payload capacity F: capacitΘ utile d'information S: cabida ·til de informaci≤n The difference between the interface rate and the interface overhead rate, that is the bit rate of the interface payload. 218 interface overhead F: rΘsidu de l'interface S: tara del interfaz The remaining portion of the bit stream after deducting the information payload. The interface over- head may be essential (e.g. framing for an interface shared by users) or ancillary (e.g. performance monitor- ing). 219 interface payload F: capacitΘ utile de l'interface S: cabida ·til del interfaz The portion of the bit stream of a framed interface which can be used for telecommunication services. Any signalling is included in the interface payload. 220 interface rate; interface bit rate F: dΘbit α l'interface; dΘbit binaire α l'interface S: velocidad del interfaz; velocidad binaria del interfaz The gross bit rate at an interface, that is, the sum of the bit rates of the interface payload and the interface overhead. Example: the bit rate at the boundary between the physical layer and the physical medium. 221 invalid cell F: cellule invalide S: cΘlula no vßlida A cell where the header is declared by the header error control process to contain errors. 222 labelled channel F: canal ΘtiquetΘ S: canal etiquetado A temporally-ordered collection of all block payloads having a common label value. 223 labelled deterministic channel F: canal ΘtiquetΘ dΘterministe S: canal etiquetado determinφstico A labelled channel with the property that the aggregated payload capacity of all blocks in each suc- cessive interval of specified constant duration is a constant. 224 labelled interface structure F: structure d'interface ΘtiquetΘe S: estructura de interfaz etiquetado An interface structure in which all services and signalling are provided by labelled channels. A labelled interface structure can be accommodated within a framed interface or a self-delineating labelled interface. 225 labelled multiplexing F: multiplexage par Θtiquetage S: multiplexaci≤n por etiquetado The multiplexing of labelled channels by concatenating the blocks of the different channels. 226 labelled statistical channel F: canal ΘtiquetΘ statistique S: canal etiquetado estadφstico A labelled channel in which the payload of the successive blocks of the channel is random and/or the block durations are random. 227 logical signalling channel F: canal logique de signalisation S: canal l≤gico de se±alizaci≤n A logical channel for signalling information which is contained within an information channel or a physical signalling channel. 228 meta-signalling F: mΘta-signalisation S: metase±alizaci≤n The procedure for establishing, checking and releasing signalling virtual channels. 229 network node interface (NNI) F: interface de noeud de rΘseau (NNI) S: interfaz de nodo de red (INR) The interface at a network node which is used to interconnect with another network node. 230 packet F: paquet S: paquete An information block identified by a label at layer 3 of the OSI reference model. 231 packet transfer mode F: mode de transfert par paquets S: modo de transferencia paquete; modo de transferencia por paquetes A transfer mode in which the transmission and switching functions are achieved by packet oriented techniques, so as to dynamically share network transmission and switching resources between a multiplicity of connections. 232 payload module F: module de capacitΘ utile S: m≤dulo de cabida ·til That portion of the information payload, of an interface, within which one or more channels entirely exist. 233 periodic frame F: trame pΘriodique S: trama peri≤dica A transmission segment which is repeated at intervals of equal duration (e.g. 125 ╡sec), and may be delineated by incorporating fixed periodic patterns into the bit stream. 234 physical frame F: trame physique S: trama fφsica A segment of a serial logical bit stream at an interface, partitioned into successive segments. 235 physical signalling channel F: canal physique de signalisation S: canal fφsico de se±alizaci≤n A dedicated physical channel (e.g. D-channel) used for signalling information. It may be used to carry other information. 236 positioned channel F: canal positionnΘ S: canal ubicado; canal identificado por su posici≤n A channel that occupies bit positions which form a fixed periodic pattern (e.g. B-, H- and D-channels in ISDN user network interfaces). 237 positioned interface structure F: structure d'interface positionnΘe S: estructura de interfaz de canales ubicados A structure in which all services and signalling are provided by positioned channels. Such a structure can exist only within a framed interface. 238 selective broadcast signalling virtual channel F: canal virtuel de diffusion sΘlective de la signalisation S: canal virtual de se±alizaci≤n de difusi≤n selectiva A virtual channel allocated to a service profile and used for broadcast signalling. 239 self-delineating block F: bloc α auto-cadrage S: bloque autodelimitado A block with the property that its endpoints can be identified by examining the block itself. A defined pattern or flag at the beginning of each block might serve to demarcate the block. 240 self-delineating labelled interface F: interface ΘtiquetΘe α auto-cadrage S: interfaz etiquetado autodelimitado An interface whose entire serial bit stream consists of a self-delineating labelled multiplexing. 241 signalling virtual channel F: canal virtuel de signalisation S: canal virtual de se±alizaci≤n A virtual channel for transporting signalling information. 242 statistical; ATM statistical F: statistique; ATM statistique S: estadφstico; MTA estadφstico A mode of the asynchronous transfer mode in which the information transfer capacity specified for a given service provided to the user throughout a call is expressed in terms of values of parameters such as mean, peak and standard deviation. 243 synchronous time division multiplexing F: multiplexage temporel synchrone S: multiplexaci≤n sφncrona por divisi≤n en el tiempo; multiplicaci≤n temporal sφncrona A multiplexing technique supporting the synchronous transfer mode(STM). 244 synchronous transfer mode (STM) F: mode de transfert synchrone (STM) S: modo de transferencia sφncrono (MTS) A transfer mode which offers periodically to each connection a fixed-length word. 245 throughput F: charge utile S: caudal de trßfico; caudal The number of data bits contained in a block (e.g. between the address field and the CRC field of the LAPD-based frames) successfully transferred in one direction across a section per unit time. 246 transfer mode F: mode de transfert S: modo de transferencia Aspects covering transmission, multiplexing and switching in a telecommunications network. 247 transit delay F: dΘlai de transit S: retardo de trßnsito The time difference between the instant at which the first bit of the address field of a frame crosses one designated boundary, and the instant at which the last bit of the closing flag of the frame crosses a sec- ond designated boundary. 248 usage parameter control F: contr⌠le des paramΦtres d'utilisation S: control de los parßmetros de utilizaci≤n The taking of appropriate action if usage monitoring establishes that the negotiated values of the information transfer parameters of a virtual channel or a virtual path are exceeded. 249 valid cell F: cellule valide S: cΘlula vßlida A cell where the header is declared by the header error control process to be free of errors. 250 virtual channel (VC) F: canal virtuel (VC) S: canal virtual (CV) A concept used to describe unidirectional transport of ATM cells associated by a common unique iden- tifier value. 251 virtual channel connection F: connexion de canal virtuel S: conexi≤n de canal virtual A concatenation of virtual channel links that extends between two points where the adaptation layer is accessed. 252 virtual channel link F: liaison de canal virtuel S: enlace de canal virtual A mean of unidirectional transport of ATM cells between a point where a virtual channel identifier value is assigned and the point where that value is translated or removed. 253 virtual path (VP) F: trajet virtuel (VP) S: trayecto virtual (TYV) A concept used to describe unidirectional transport of ATM cells belonging to virtual channels that are associated by a common identifier value. 254 virtual path connection F: connexion de trajet virtuel S: conexi≤n de trayecto virtual A concatenation of virtual path links that extends between the point where the virtual channel iden- tifier values are assigned and the point where those values are translated or removed. 255 virtual path link F: liaison de trajet virtuel S: enlace de trayecto virtual The group of virtual channel links, identified by a common value of the virtual path identifier, between the point where the VPI value is assigned and the point where the VPI value is translated or removed. ANNEX A (to Recommendation I.113) Alphabetical list of terms contained in this Recommendation1) 201 asynchronous time-division multiplexing 202 asynchronous transfer mode 203 block 204 block payload 101 broadband [wideband] 205 broadband access 206 broadband communication channel 102 broadcast 207 cell 208 cell delineation 209 circuit transfer mode 210 connection admission control 103 connectionless service 104 constant bit rate service 105 contribution; contribution application 106 conversational service 211 deterministic; ATM deterministic 108 distribution service 109 distribution service with user individual presentation control 110 distribution service without user individual presentation control 107 distribution; distribution application 111 enhanced-quality television 112 existing-quality television 212 frame 213 frame interface 214 general broadcast signalling virtual channel 215 header; cell header 216 hybrid interface structure 217 information payload capacity 113 interactive service 218 interface overhead 219 interface payload 220 interface rate; interface bit rate 221 invalid cell 222 labelled channel 223 labelled deterministic channel 224 labelled interface structure 225 labelled multiplexing 226 labelled statistical channel 227 logical signalling channel 114 messaging service 228 meta-signalling 115 mixed document 116 multimedia service 117 multipoint 229 network node interface 230 packet 231 packet transfer mode 232 payload module 233 periodic frame 234 physical frame 235 physical signalling channel 236 positioned channel 237 positioned interface structure 118 post-production processing 119 retrieval service 238 selective broadcast signalling virtual channel 239 self-delineating block 240 self-delineating labelled interface 120 service bit rate 241 signalling virtual channel 121 sound retrieval service 242 statistical; ATM statistical 243 synchronous time division multiplexing 244 synchronous transfer mode 245 throughput 246 transfer mode 247 transit delay 248 usage parameter control 249 valid cell 122 variable bit rate service 123 videomessaging 250 virtual channel 251 virtual channel connection 252 virtual channel link 253 virtual path 254 virtual path connection 255 virtual path link ANNEX B (to Recommendation I.113) List of abbreviations used in B-ISDN Recommendations AAL ATM Adaptation Layer AAL-PCI AAL protocol control information AAL-SDU AAL service data unit ACE Access connection element AIS Alarm indication signal AL Access Link ATM Asynchronous transfer mode ATM-SDU ATM service data unit AU Administrative unit B-ISDN Broadband aspects of integrated services digital network B-ISDN PRM Protocol reference model of the broadband aspects of ISDN B-ISPBX Private branch exchange for B-ISDN B-NT Network termination for B-ISDN B-NT1 Network termination 1 for B-ISDN B-NT2 Network termination 2 for B-ISDN B-TA Terminal adaptor for B-ISDN B-TE Terminal equipment for B-ISDN BER Bit error ratio BIP Bit interleaved parity BOM Beginning of message C-n Container-n CAD-CAM Computer aided design/computer aided manufacturing CAMC Customer access maintenance centre CBR Constant bit rate CE Connection element CEQ Customer equipment CIME Customer installation manintenance entities CL Connectionless CLP Cell loss priority CLSF Connectionless service function CMI Coded mark inversion CN Customer network COH Connection overhead COM Continuation of message CON Concentrator CRC Cyclic redundancy check CRF Connection related function CRF(VC) Virtual channel connection related function CRF(VP) Virtual path connection related function CS Convergence sublayer CS-PDU Convergence sublayer protocol data unit DPL Primary link for distribution services DS Digital section EOM End of message ET Exchange termination FDDI Fibre distributed data interface FEBE Far end blok error FERF Far end receive failure GFC Generic flow control HDLC High-level data link control HDTV High definition television HEC Header error control HLF Higher layer function IPL Primary link for interactive services IRP Internal reference point IT Information type LAN Local area network LE Local exchange LFC Local function capabilities LI Length indicator LT Line termination MA Medium adaptor MAN Metropolitan area network MCD Maintenance cell description MID Multiplexing identification MSB Most significant bit MSP Maintenance service provider MUX Multiplexor NNI Network-node interface NP Network performance NT Network termination OAM Operation and maintenance OAMC Operation, administration and maintenance centre OSI Open systems interconnection PCI Protocol control information PDH Plesiochronous digital hierarchy PDU Protocol data unit PL Physical layer PL-OAM Physical layer-operation and maintenance (cell) PLK Primary link PM Physical medium (sublayer) POH Path overhead PON Passive optical network PRM Protocol reference model PT Payload type PTR Pointer QOS Quality of service RAI Remote alarm indication RES Reserved RG Regenerator RPOA Recognized private operating agency RS Regenerator section RU Remote unit SAP Service access point SAR Segmentation and reassembly sublayer SDH Synchronous digital hierarchy SDU Service data unit SFET Synchronous frequency encoding technique SN Sequence number SN Sequence number protection SOH Section overhead SP Service provider SPL Service provider link SPN Subscriber premises network SSM Single segment message ST Segment type STM Synchronous transfer mode STM-n Synchronous transport module-n SVC Signalling virtual channel TA Terminal adaptor TC Transmission convergence sublayer TCE Transit connection element TCRF Transit connection related function TE Terminal equipment TMN Telecommunication management network TPE Transmission path endpoint UNI User-network interface VBR Variable bit rate VC Virtual channel VC Virtual container-n VCC Virtual channel connection VCCE Virtual channel connection endpoint VCI Virtual channel identifier VP Virtual path VPC Virtual path connection VPCE Virtual path connection endpoint VPI Virtual path identifier